Compositions and methods for maintenance of bone health or prevention, alleviation andor treatment of bone disorders are presented. The wireless charging circuit includes a boost DC to DC converter, a unidirectional conductive element and a wireless power converter. The cell phone further comprises: a battery for supplying power; a display module, connected to the storage module and the battery respectively, for displaying the data information using power remaining in the battery when the cell phone is in a power-off state. In exemplary embodiments, the inner core region is made of a low dielectric material, and the outer regions include alternating layers of low and high dielectric materials. In a specific embodiment, the P absorber layer has a P\u2212 type impurity characteristics and a first optical absorption coefficient greater than 104 cm\u22121 in a wavelength range comprising 400 nm to 800 nm.